AU = 1.496e13               # cm
pc = 3.086e18               # cm
ly = 9.463e17               # cm
M_sun = 1.99e33             # g
R_sun = 6.955e10             # cm
L_sun = 3.9e33              # erg s^-1
T_sun = 5.78e3              # K
Jy = 1.0e-23                # erg s^-1 cm^-2 Hz^-1
arcsec = 4.84813681e-6      # radians
kms = 1e5
